Advice needed, Need a new telelens for my Canon 7D

I can speak about the 400 f/5,6 which I have about 8 years ago, used on film and digital, and I can say it´s a wonderful lens. It´s size, weight and cost makes it a jewel. It´s really sharp wide open, the way you will use it 90 % of the time.

You have to bear in mind that it´s not a zoom, and sometimes, you can find yourself wanting less or more focal, but you can attach it with teleconverters. By the way, use with 1,4X only when needed because of the loss of IQ (about 20% IQ estimated). I never used it with 2X, because I find 1,4X is the limit.

The AF is a little bit slow if we compare it with the more modern lenses such as 70-200 IS f/4, but it´s not bad at all. I use it with 1DIV and 5dIII.

The only con for me is the lack of IS.

Some says that this year a new version with IS will be launched, as well as the new 100-400. No dates are said, but if it´s not an imminent buy, you should follow them.